One of the inevitable outcomes of moves like this is that it becomes a tool of cliquedom.

On some of the forums I see where this operates, it very clearly starts off well intentioned but inevitably becomes less a tool of post approval but more a took of poster approval and disapproval. It then also eventually becomes a tool of groups of people to mutually support each other when they attack other mutually disliked people or perceived enemies. All of us have experienced the distinct feeling that once you have disagreed with another poster, nothing you ever say in future will not prompt disagreement.

I understand why people think this is a progressive step but eventually it takes away more than it adds in my view and I believe will harm rather than improve FT.